Backend Engineer


python flask fintech London


In the stock market, trading is done electronically by robots, news is instant, data is abundant. In the world of high yield bonds, trading is done by humans over the phone, news takes 20 minutes to hit the market and data sucks.

Using machine learning and computer vision we're building a 'technology first' data, news and analytics platform for high yield bonds. The debt capital markets behave like it's still the 1980s. 9fin aims to fix that.

p.s. We're in beta testing, backed by VCs + hiring to grow our team...


1. Technology doesn’t serve the business.Technology is the business.

Technology and business are not independent; they are one and the same. We’ve met CEOs who don’t know what language their code is written in and CTOs who don’t know who the customers are. That’s not OK.

2. Talent trumps experience.

We judge people by the quality of their ideas, not the duration of their employment. We’d rather work with people who have spent 12 months being awesome than those who have spent 3 years being average.

3. Don’t know? Say so.

Ignorance is only a weakness when you don’t admit it. We’ve seen lots of people waste hours of productivity because they were too afraid to ask for help.

4. Ship early and often.

It’s impossible to design a truly awesome product without customer feedback.

5. Never settle.

The product might have shipped, but it’s never perfect. If we can’t find ways to improve we just aren’t looking hard enough.

6. Diversity.

We don’t discriminate. As well as being an end in itself, varied backgrounds and cultures bring new perspectives and stop group think.

7. Have an opinion.

No decision is off limits to being challenged. Disagreement is healthy, it shows you care.

8. Beautiful simplicity.

If it’s not easy to use, then it’s broken. Consumer applications relentlessly focus on the user with beautiful interfaces and snazzy graphics. There’s no reason why B2B can’t be just as good.

9. Make time for others.

Everyone is busy. But taking 5-10 minutes out of your day to grab a coffee with a colleague who needs advice or help is not too much to ask.

10. Overcommunicate.

Don’t leave people in the dark. It’s better to receive a 10 second note saying “Super busy, but I’ll get to it.” than radio silence.

11. Family & health come first.

No customer or job matters more than family and your health.


Every member of the technology team works with these responsibilities in mind

Code Quality: Through writing testable, maintainable code, and by engaging in code review for your own work and for reviewing others

Deployment, Operations and Support: We all play a part in supporting our customers. On the development side we ensure the code we write is simple to deploy, monitor and manage

Security: Writing secure code by following well-worn best practices and design patterns. Applying the principles of least trust, least privilege and elevated authentication for elevated access. Taking time to specifically focus on security in code reviews


  • Develop and engineer primarily on services and infrastructure of the platform
  • Take on and fix prioritised issues from the issue tracker
  • Write code delivering new service functionality, implementing API’s, data routing/processing, automation and deployment mechanisms
  • Continually improve on the 9fin codebase taking the chance to automate, refactor and document when you can


  • Know how to effectively think and reason about your software, algorithms used and performance at a high level
  • Be able to think about how data will pass through your code from persistent storage to API endpoint
  • Have previous experience or are interested in learning about capital markets technology and the fixed income industry
  • Have production-level (i.e. deployed and used) experience with Python and its web frameworks
  • Familiar with RDBMS and how to write SQL statements for retrieving data
  • Experience with linux systems, containerization, cloud services a plus but not mandatory
  • Be able to collaborate with product and other engineers
  • Strong written and verbal communication
  • A take home technical task is part of the hiring process for this position

Salary range £25,000 — 45,000

Dependent on experience